Numerous attempts have been made so far to solve the problem of the electrical insulation in building machines of the above mentioned type.
To improve the electrical insulation in motor-reducers used in building machines such as mixers and stirrers, a first approach is to insert the motor-reducer assembly within a cabin made of plastics material and containing all the above components. This solution, however, implies increased overall dimensions of the machine's part housing the motor and reducer.
A further attempt to solve the problem of the electrical insulation in a motor-reducer provides for separating the electric motor from the reducer, insulating only the motor and connecting the latter to the reducer via drive belts made of insulating material. This solution does not allow a direct connection between the motor and the reducer.